1. Field of Invention
This invention relates to an improvement in oil pumps for internal combustion engines, and more particularly, to an improvement in oil pumps for HARLEY-DAVIDSON 74 and 80 cubic inch twin-v-engines.
2. Description of Related Art
Low oil pressure is a common problem in HARLEY-DAVIDSON 74 and 80 cubic inch twin-v-engines, using the aluminum bodied, rotary gear oil pump. This design of oil pump. U.S. Pat. No. 2,111,242 Harley, utilizes a pressure relief valve to control the oil pressure that is supplied to the engines. This design of said oil pump is used on all HARLEY-DAVIDSON 74 and 80 cubic inch twin-v-engines.
Referring now to U.S. Pat. No. 3,912,045 Morris, which describes a different design of oil pump rather than the rotary gear, pressure relief type. The said patent goes into detail of how the pressure relief spring controls the oil pressure from the relief valve in a rotary gear type pump.
Briefly, in accordance with U.S. patent application No. 07/645,620 Emmitt, said patent application uses a pressure relief spring of different lengths to increase the biasing means between the pressure relief plunger and the pressure relief cap. With the said spring being the biasing force that holds the said plunger closed until sufficient pressure is obtained that will lift the said plunger, opening an oil passage, thus controlling the oil pressure of the HARLEY-DAVIDSON aluminum bodied, rotary gear oil pump. By increasing the biasing means, the biasing force upon said plunger is increased, which increases the oil pressure.
Although, the motorcycle industry or aftermarket companies have introduced oil pumps of the said design, with a few changes, they are quite expensive and still do not address the problem of low pressure.
It is the purpose of this invention to provide a lubricating system which dramatically improves and precisely meters the oil in the HARLEY-DAVIDSON 74 and 80 cubic inch twin-v-engine, while still utilizing the stock HARLEY-DAVIDSON oil pump.
No device is known, however, that effectively improves and precisely meters oil in the stock and stock style of the HARLEY-DAVIDSON oil pump.